Decimal point mechanism



Oct. 30, 1956 R. v. REPPERT DECIMAL POINT MECHANISM 2 Sheets-Sheet 1 Filed Dec. 15, 1954 Oct. 30, 1956 R. v. REPPERT DECIMAL POINT MECHANISM 2 Sheets-Sheet 2 Filed Dec. 15, 1954 x m N. m

XN O m N m m XN O m N m X O m N m l 3 82 3 x on 5 0:56

United States Patent DECIMAL POINT MECHANISM Richard V. Reppert, Rochester, N. Y. Application December 13, 1954, Serial No. 474,879 4 Claims. (Cl. 235-79) This invention relates to improvements in decimal point mechanisms for calculating machines, and has as its object the improvement and simplification of such mechanisms.

The present decimal point mechanism is an adjunct or auxiliary mechanism for the calculating machine shown and described in my copending application, Serial No. 175,990, now Patent No. 2,702,159, granted February 15, 1955; and reference is to be had to this application for a detailed description thereof.

In said copending application, a series of ordinal decimal point indicators for the register dials are provided and are subject to selection and setting operation, to set an indicator to indicate the decimal point of a product displayed in the register dials, resulting from the indexing operation of the keys, followed by the multiplying operation.

For the purpose of this application, the decimal point indicators shown in said copending application have been retained, but the means of selecting and setting an indicator have been improved and simplified.

In the drawings:

Figure 1 is a longitudinal sectional elevation.

Figure 2 is a fragmentary front elevation of the register section, showing the register dials and the decimal point indicator mechanism.

Figure 3 is a section through the selector cam shaft for the decimal point indicators.

Figure 4 is a detail of the stop disc for the selector cam shaft.

Figure 5 is an enlarged detail of the mechanism by which the selector shaft is moved in angular units.

Figure 6 is a detail of the M key.

Figure 7 is a detail of the clear key.

Figure 8 is a detail of the multiplier decimal point key.

Figure 9 shows two multiplying examples.

Figure 10 is a circuit diagram for the multiplicand and multiplier keys.

As stated above, the decimal point mechanism of the present invention is an adjunct or auxiliary mechanism for the calculating machine shown in my copending application Serial No. 175,990, now Patent No. 2,702,159. Parts of the machine of said copending application and patent are shown in Fig. 1 of the present application. This machine has a series of register gears 119 that operate dials 122. These gears 119 are operable by the intermediate gears 118, which in turn, are operated by the racks 113. An actuating mechanism is provided for each rack 113 and comprises the members 95, 91, 92, 93, 1195, 107, 90 and 106. These actuating mechanisms are actuated and cooperate as fully described in said copending application and patent. They are supported by the transverse bracket 94 and are under the control of a pin carriage 13 which has rows of pins 10 that are settable by a key mechanism comprising the members 4, 5, 7 and 8, Whose construction and operation is also fully described in said copending application and patent. The carriage 13 is movable by a spring 23; and a poweroperated reset mechanism is provided for the carriage comprising the members 520, 530.

As described in said copending application, the multiplicand keys 1 are operated to close contacts 3 for the magnets 4 that set the multiplicand members 10 in the carriage 13 in position to represent a multiplicand and also to escape the carriage step by step to position the multiplicand members, in succession, in operative relation with the setting devices.

The said magnets 4 have a common return conductor extending to the magnet 27 which operates the escapement for the multiplicand carriage, as shown in Figure 3 of said application and for the purpose of this application, a branch conductor extends from the return conductor to a magnet 675 which operates the decimal point indicating mechanism. See Figure 10.

As further described in said copending application, the multiplier keys 200, Fig. 10, are operated to close contacts 199 for the magnets 240 that set the multiplier members (not shown) in position to represent a multiplier, Fig. 10. Reference may be had to said copending application and patent for the structure of the multiplier members themselves. The magnets have a common return conductor (not shown), which operates the carriage (not shown) of the multiplier mechanism; as shown in Figure 7 of said copending application and patent. For the purpose of the present application, a branch conductor extends to the magnet 676 which operates the decimal point indicator setting mechanism.

The said two magnets 675 and 676 operate a selector shaft 677 mounted in the side plates of the register sections, and this shaft is rotatable in angular units or steps to set the decimal point indicators to indicating position. See Figure 2. The ordinal decimal point indicators 65 are pivoted on levers 60 mounted on shaft 61 extending between the section side plates, and small follower cams 689 are formed on the levers and cooperate with cams 678 on the rotatable selector shaft 677. The cams 678 are spaced to align with the levers 60 and are mounted in a helix on the periphery of the shaft. See Figure 2.

As stated, the selector shaft is rotatable in angular units or steps to thereby cause cooperation of the cams and levers in ordinal sequence. The selector shaft is held in normal position by a spring 679, which holds a stop disc 6S1, mounted on the shaft hub 683, against a stop pin on the section plate.

See Figures 1 and 2. A ratchet wheel 684 is mounted on the shaft hub 683 and is engaged by a feed pawl 685 pivoted 0n the lever 687 which is operable by the magnets 675 and 676 to rotate the shaft in step movements and thereby operate the indicator levers in ordinal succession. Normally the cam of highest order holds the indicator of highest order in upper or set position, as shown in Figure 3; and for every step movement of the shaft, the indicator of next lower order is set and the one of higher order is reset.

In order to simplify the circuit, it is provided that the lever 687 is operable by either of the two magnets 675 and 676 and respectively by the operation of the multiplicand and multiplier digit keys. A spring 704 tends to hold the lever 687 against the stop plate 690, and a holding detent 691 engages the ratchet wheel 684 to hold the shaft against reset movement until the magnet 692 is operated by the C or clear key and operates the detent 691 and the pawl 685 to disengage the ratchet wheel for reset movement.

A multiplicand decimal point key 33 is provided and is operable in its proper sequence when the multiplicand digit keys are operated to index the multiplicand, to open the contact 701, and thereby open the circuit extending from the multiplicand digit keys to the magnet 675 which operates-the selector shaft 677 for the decimal point indicators. The decimal point key is locked in set position by the'detent-699 and thereby the circuit is held open, so that the operation of the selector shaft to set indicators is terminated. The operation of the C or clear key closes the circuit for the magnet 698 which operates the detent 699, to release the key for reset movement.

A multiplier decimal point key 201 is provided and is operable in its proper sequence when the multiplier digit keys are operated to index the multiplier, to open the contact 694, and thereby open the circuit for the magnet 6.76 which operates the selector shaft for the decimal point indicators, thereby terminating the operation of the selector shaft by the multiplier digit keys. The key is locked in set position by the detent 6%, held in position by the spring 697; and, upon operation of the C key, the magnet 686 operates the detent to re lease the key for resetting movement.

As stated, the decimal point indicating mechanism is operated to set the indicators in sequence, starting with the indicator of highest order; and, in order to synchronize the operation of the decimal point mechanism with the operation of actuators for the register dials, the multiplicand carriage is moved to position the multiplicand devices of highest order into operative relation with the actuators of highest order.

As fully described in said copending application, an M key is provided and is operable to initiate multiplying operation; and, for the purpose of this application, it is provided that the operation of the M key causes the multiplicand carriage to be moved to position the multiplicand devices of highest order in operative rela tion with the actuators for the register dials of highest order. In a copending application, Serial No. 427,752, it is fully described how the operation of the M key positions the multiplicand carriage, as stated.

In Figure 9, two multiplying examples are shown. The left-most register dial receives only transfer movement, and therefore the second dial is the dial of highest order subject to operation by the actuators for the register dials. The multiplicand is set up in ordinal sequence in the multiplicand carriage by the operation of the digit keys, and the carriage is then moved to position the multiplicand devices of highest order into operative position with the actuators of highest order so that the multiplicand devices representing the multiplicand figure 37.50 are aligned as shown in the first line below the dials, in the first example.

The digit keys are operated to index the multiplicand digits 37, then the multiplicand decimal point key is op- 'erated, and then the digits 50 are indexed. Next, the digits 4 and 2 of the multiplier 42.20 are indexed, then the multiplier decimal point key is operated, and then the digits 2 and are indexed. The M key is then operated to initiate multiplying operation. The operation of the four digit keys 3, 7 and 4, 2 has raised, or positioned, the indicator 65 that is located four orders to the right, from the highest order position, as shown in solid black in said figure. In its first position, the multiplicand is added four times, as indicated in line 1, and then the multiplicand is automatically backspaced one order, as fully described in said copending application 175,990, and, in this position, is added twice, as shown in line 2. Again the multiplicand is backspaced one order and then added twice, as shown in line 3. The register dials will then stand as shown in line 4: 1582.50.

The operation of the keys for the second example, .375 times .156, requires the operation of the decimal point key as the first key of the multiplicand and the multiplier; and, as a result thereof, the indicator mechanism is not operated and the indicator 'for the first dial remains in its normal set position, as indicated in solid black. Both decimal point keys have been operated and thereby have disabled the indicator-setting mechanism. The multiplicand is added in the same manner as described for the first example and as indicated. The product, .05850, will appear in the dials at the conclusion of the multiplying operation.

Figure 10 is a circuit diagram showing the circuits controlled by the operation of the multiplicand and multiplier key boards. The operation of a multiplicand digit key closes the respective contact 3 and energizes the respective magnet 4 to index the multiplicand digit. The common return line extends to the magnet 27 that opthe escapernent for the multiplicand carriage. A branch line extends from the common return line to the normally closed contact 701 and then to the magnet 675 that operates the selector shaft of the decimal point mechanism. Operation of the decimal point key opens the contact 701 and thereby terminates the operation of the selector shaft.

The operation of a multiplier digit key closes the respective contact 199 and energizes the respective magnet 2413 to index the multiplier digit. The common return line extends to the magnet 264 that operates the escapement for the multiplier carriage, as fully described in said copending application. A branch line extends from the common return line to the normally closed contact 6M- and then to the magnet 676 that operates the selector shaft of the decimal point mechanism. Operation of the decimal point key opens the contact 694 and thereby terminates the operation of the selector shaft.

What I claim is:

1. in a calculating machine having ordinal register dials, ordinal actuators for the register dials, multiplicand devices to select the actuators for operation and to control the extent of their movement, multiplicand digit keys operable to index the multiplicand, multiplier devices to control the multicyclic operation of the actuators, multiplier digit keys operable to index the multiplier, ordinal decimal point indicators for the register dials, settable to indicating position; the combination of a setting device for the indicators operable in step movements to set and reset the indicators in successive steps, and in ordinal sequence, from highest to lowest order, with the indicator of highest order normally in set position, means under control of the multiplicand digit keys when operated to index a multiplicand, to impart step movement to the setting device, whereby it is moved one step for each operation of a multiplicand digit key, a multiplicand decimal point key, means under control of the multiplicand decimal point key when operated in its proper sequence when the multiplicand is indexed, to disable the aforesaid means for imparting step movement to the setting device, means operable by the multiplier keys when operated to index the multiplier to impart step movement to the setting device, whereby it is moved one step for each operation of a multiplier digit key, a multiplier decimal point key, operable in its proper sequence when the multiplier is indexed, and means under control of the multiplier decimal point key to disable the lastnamed means to impart step movement to the setting device.

2. In a calculating machine having ordinal register dials, ordinal actuators for the register dials, multiplicand devices to select the actuators for operation and to control the extent of their movement, multiplicand digit keys operable to index the multiplicand, multiplier devices to control the multicyclic operation of the actuators, multiplied digit keys operable to index the multiplier, ordinal decimal point indicators for the register dials, settable to indicating position; the combination of setting devices for the indicators and comprising a rotatable selector shaft subject to angular step movement, means on said shaft to set and reset the indicators in succession and in ordinal sequence, to and from indicating position, means under control of the multiplicand digit keys when operated to index a multiplicand to impart step movement to said shaft whereby it receives an angular step movement for each operation of a multiplicand digit key, a multiplicand decimal point key, means under control of the multiplicand decimal point key when operated in its proper sequence when the multiplicand is indexed, to disable the aforesaid means for imparting step movement to the said shaft, means operable by the multiplier keys when operated to index the multiplier and to impart step movement to the selector shaft, whereby it is moved one angular step for each operation of a multiplier digit key, a multiplier decimal point key operable in its proper sequence when the multiplier is indexed and means under control of the multiplier decimal point key to disable the last-named means for imparting step movement to the selector shaft.

3. In a calculating machine having ordinal register dials, ordinal actuators for the dials, ordinal decimal point indicators for the dials settable to indicating position, multiplicand devices to select the actuators and control the extent of their movement and comprising digit keys operable to index the multiplicand, multiplier devices operable to control the multicyclic operation of the actuators, comprising digit keys operable to index the multiplier, the combination of a setting device for the decimal point indicators, operable to set the indicators in succession and in ordinal sequence from highest to lowest order, means under control of the multiplicand digit keys to operate the setting device, a multiplicand decimal point key operable in its proper sequence when the multiplicand is indexed, means under control of the decimal point key to disable the aforesaid means under control of the multiplicand digit keys to operate the setting device for the indicators, means under control of the multiplier digit keys to operate the setting device, a multiplier decimal point key operable in its proper sequence when the multiplier is indexed, and means under control of the multiplier decimal point key to disable the means under \control of the multiplier digit keys to operate the setting device for the indicators.

4. In a calculating machine having ordinal register dials, actuators for the register dials, ordinal decimal point indicators for the register dials, settable to indicating position, multiplicand devices to select the actuators and control the extent of their movement and comprising digit keys operable to index the multiplicand, multiplier devices operable to control the multicyclic operation of the actuators and comprising digit keys operable to index the multiplier, the combination of a setting device for the decimal point indicators and comprising a cam shaft rotatable in rotary unit movements, a series of ordinal cams mounted on said shaft in helical arrangement and in operative relation to the indicators, so that rotation of the shaft sets and resets the indicators in ordinal sequence from highest to lowest order, leans under control of the multiplicand digit keys to cause a rotary movement of the shaft of as many units as keys are operated, a multiplicand decimal point key operable in its proper sequence when the multiplicand is indexed, means under control of the decimal point key to disable the said means under control of the digit keys to cause rotation of the cam shaft, means under control of the multiplier digit keys to cause as many units of rotary movements of the shaft as keys are operated, a multiplier decimal point key operable in its proper sequence when the multiplier is indexed, and means under control of the multiplier decimal point key to disable the said means under control of the multiplier digit keys to cause rotation of the cam shaft.

References Cited in the file of this patent UNITED STATES PATENTS 1,503,742 Bacon Aug. 5, 1924 2,329,190 Ellerbeck Sept. 14, 1943 2,329,218 Reynolds Sept. 14, 1943 2,467,419 Avery Apr. 19, 1949 2,673,684 Reppert Mar. 30, 1954 2,702,159 Reppert Feb. 15, 1955 

